From 079811984cd952714e6cf85297c91830c0790a1d Mon Sep 17 00:00:00 2001
From: jordan4ibanez <jordan4ibanez@users.noreply.github.com>
Date: Sat, 24 Apr 2021 23:29:56 -0400
Subject: [PATCH] Make every mob besides spiders get slowed down by cobwebs
 like players

---
 mods/ENTITIES/mcl_mobs/api/api.lua            |  2 ++
 .../mcl_mobs/api/mob_functions/ai.lua         | 24 +++++++++++++++++++
 .../mcl_mobs/api/mob_functions/movement.lua   | 15 ++++++++++++
 mods/ENTITIES/mobs_mc/spider.lua              |  1 +
 4 files changed, 42 insertions(+)

diff --git a/mods/ENTITIES/mcl_mobs/api/api.lua b/mods/ENTITIES/mcl_mobs/api/api.lua
index 4cc49e322..f1497c474 100644
--- a/mods/ENTITIES/mcl_mobs/api/api.lua
+++ b/mods/ENTITIES/mcl_mobs/api/api.lua
@@ -359,6 +359,8 @@ function mobs:register_mob(name, def)
 
 		--fire timer
 		burn_timer = 0,
+
+		ignores_cobwebs = def.ignores_cobwebs,
 		--end j4i stuff
 
 		-- MCL2 extensions
diff --git a/mods/ENTITIES/mcl_mobs/api/mob_functions/ai.lua b/mods/ENTITIES/mcl_mobs/api/mob_functions/ai.lua
index a2e48ba2a..b79eaf665 100644
--- a/mods/ENTITIES/mcl_mobs/api/mob_functions/ai.lua
+++ b/mods/ENTITIES/mcl_mobs/api/mob_functions/ai.lua
@@ -1035,6 +1035,30 @@ mobs.mob_step = function(self, dtime)
 		mobs.collision(self)
 	end
 
+	--overrides absolutely everything
+	--mobs get stuck in cobwebs like players
+	if not self.ignores_cobwebs then
+
+		local pos = self.object:get_pos()
+		local node = minetest_get_node(pos).name
+		
+		if node == "mcl_core:cobweb" then
+
+			--fight the rest of the api
+			if self.object:get_acceleration().y ~= 0 then
+				self.object:set_acceleration(vector_new(0,0,0))
+			end
+
+			mobs.stick_in_cobweb(self)
+
+		else
+			--return the mob back to normal
+			if self.object:get_acceleration().y == 0 and not self.swim and not self.fly then
+				self.object:set_acceleration(vector_new(0,-self.gravity,0))
+			end
+		end
+	end
+
     self.old_velocity = self.object:get_velocity()
 	self.old_pos = self.object:get_pos()
 end
diff --git a/mods/ENTITIES/mcl_mobs/api/mob_functions/movement.lua b/mods/ENTITIES/mcl_mobs/api/mob_functions/movement.lua
index 916563832..dbc984819 100644
--- a/mods/ENTITIES/mcl_mobs/api/mob_functions/movement.lua
+++ b/mods/ENTITIES/mcl_mobs/api/mob_functions/movement.lua
@@ -10,6 +10,7 @@ local vector_new      = vector.new
 local vector_length   = vector.length
 local vector_multiply = vector.multiply
 local vector_distance = vector.distance
+local vector_normalize = vector.normalize
 
 local minetest_yaw_to_dir = minetest.yaw_to_dir
 local minetest_dir_to_yaw = minetest.dir_to_yaw
@@ -19,6 +20,20 @@ local DEFAULT_FLOAT_SPEED = 4
 local DEFAULT_CLIMB_SPEED = 3
 
 
+mobs.stick_in_cobweb = function(self)
+	local current_velocity = self.object:get_velocity()
+	
+	local goal_velocity = vector_multiply(vector_normalize(current_velocity), 0.4)
+
+	goal_velocity.y = -0.5
+
+	local new_velocity_addition = vector.subtract(goal_velocity,current_velocity)
+
+	--smooths out mobs a bit
+	if vector_length(new_velocity_addition) >= 0.0001 then
+		self.object:add_velocity(new_velocity_addition)
+	end
+end
 
 --this is a generic float function
 mobs.float = function(self)
diff --git a/mods/ENTITIES/mobs_mc/spider.lua b/mods/ENTITIES/mobs_mc/spider.lua
index 09cbba5a7..67de9250d 100644
--- a/mods/ENTITIES/mobs_mc/spider.lua
+++ b/mods/ENTITIES/mobs_mc/spider.lua
@@ -26,6 +26,7 @@ local spider = {
 	reach = 2,
 	hp_min = 16,
 	hp_max = 16,
+	ignores_cobwebs = true,
 	xp_min = 5,
 	xp_max = 5,
 	eye_height = 0.475,